1. Field of the Invention
The present invention relates to a surface light source of a direct-type backlight unit, and more particularly, to a direct-type backlight unit in which a unit surface light source composed of a light emitting device is mounted on a board by a chip-on-board technique, thereby manufacturing the backlight unit easily in a simpler process.
2. Description of the Related Art
With development in the electronic device industry, a liquid crystal display (LCD) is highlighted as a next-generation display device. The LCD does not generate light on its own, thus typically requiring a backlight unit for backlighting an LCD panel.
This backlight unit includes an edge-type and direct-type backlight unit. In the former, light generated from a light source is emitted sideward and then directed upward through a reflective plate or a diffusing pattern to be irradiated onto the liquid crystal panel. In contrast, in the latter, the light source is disposed below the liquid crystal panel to emit light sideward. Then the light is directed upward through a reflective sheet to be irradiated onto the liquid crystal panel.
FIG. 1 is a schematic view illustrating an example of a conventional direct-type backlight unit.
Referring to FIG. 1, a liquid crystal display 100 includes a direct-type backlight unit 104, a planar surface optical device 120, and a display device 102. The backlight unit 104 includes a board 106 and a plurality of LEDs 108 to 118 disposed thereon.
Light generated from the LEDs 108 to 118 is diffused through a diffusing plate 122 disposed below the planar optical device 120 while propagating through the planar optical device 120. Then the light backlights the display device 102.
The conventional backlight unit 104 has the LEDs 108 to 118 individually disposed on the board 106 to form a surface light source. This entails a time-consuming process and higher manufacturing costs.